Use of content interface for sharing files (read-only)

snapcraft
3

Hi again,
I am not sure how this is supposed to work.
I followed the steps.

Here is my producer snap (epizaphost)

slots:
  zaphost-logfile:
    interface: content
    content: mydirectory
    read:
      - $SNAP_DATA/log

Here is my consumer snap (epigateway)

plugs:
    zaphost-logfile:
        interface: content
        content: mydirectory
        target: $SNAP_DATA/log
        default-provider: epizaphost

They are connected
epizaphost:zaphost-logfile epigateway:zaphost-logfile

There is a file ZapHost.log in $SNAP_DATA/log of epizaphost.
I want the epigateway snap to be able to read it.
However it is not accessible in $SNAP_DATA/log now?